1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146

use std::{cell::Cell, collections::VecDeque, sync::Arc};

use floem_reactive::{create_effect, untrack, with_scope, ReadSignal, Scope, Trigger, WriteSignal};
use once_cell::sync::Lazy;
use parking_lot::Mutex;

use crate::{
    app::UserEvent,
    window_handle::{get_current_view, set_current_view},
    Application,
};

pub(crate) static EXT_EVENT_HANDLER: Lazy<ExtEventHandler> = Lazy::new(ExtEventHandler::default);

#[derive(Clone)]
pub struct ExtEventHandler {
    pub(crate) queue: Arc<Mutex<VecDeque<Trigger>>>,
}

impl Default for ExtEventHandler {
    fn default() -> Self {
        Self {
            queue: Arc::new(Mutex::new(VecDeque::new())),
        }
    }
}

impl ExtEventHandler {
    pub fn add_trigger(&self, trigger: Trigger) {
        EXT_EVENT_HANDLER.queue.lock().push_back(trigger);
        Application::with_event_loop_proxy(|proxy| {
            let _ = proxy.send_event(UserEvent::Idle);
        });
    }
}

pub fn create_ext_action<T: Send + 'static>(
    cx: Scope,
    action: impl FnOnce(T) + 'static,
) -> impl FnOnce(T) {
    let view = get_current_view();
    let cx = cx.create_child();
    let trigger = cx.create_trigger();
    let data = Arc::new(Mutex::new(None));

    {
        let data = data.clone();
        let action = Cell::new(Some(action));
        with_scope(cx, move || {
            create_effect(move |_| {
                trigger.track();
                if let Some(event) = data.lock().take() {
                    untrack(|| {
                        let current_view = get_current_view();
                        set_current_view(view);
                        let action = action.take().unwrap();
                        action(event);
                        set_current_view(current_view);
                    });
                    cx.dispose();
                }
            });
        });
    }

    move |event| {
        *data.lock() = Some(event);
        EXT_EVENT_HANDLER.add_trigger(trigger);
    }
}

pub fn update_signal_from_channel<T: Send + 'static>(
    writer: WriteSignal<Option<T>>,
    rx: crossbeam_channel::Receiver<T>,
) {
    let cx = Scope::new();
    let trigger = cx.create_trigger();

    let channel_closed = cx.create_rw_signal(false);
    let data = Arc::new(Mutex::new(VecDeque::new()));

    {
        let data = data.clone();
        cx.create_effect(move |_| {
            trigger.track();
            while let Some(value) = data.lock().pop_front() {
                writer.try_set(value);
            }

            if channel_closed.get() {
                cx.dispose();
            }
        });
    }

    let send = create_ext_action(cx, move |_| {
        channel_closed.set(true);
    });

    std::thread::spawn(move || {
        while let Ok(event) = rx.recv() {
            data.lock().push_back(Some(event));
            EXT_EVENT_HANDLER.add_trigger(trigger);
        }
        send(());
    });
}

pub fn create_signal_from_channel<T: Send + 'static>(
    rx: crossbeam_channel::Receiver<T>,
) -> ReadSignal<Option<T>> {
    let cx = Scope::new();
    let trigger = cx.create_trigger();

    let channel_closed = cx.create_rw_signal(false);
    let (read, write) = cx.create_signal(None);
    let data = Arc::new(Mutex::new(VecDeque::new()));

    {
        let data = data.clone();
        cx.create_effect(move |_| {
            trigger.track();
            while let Some(value) = data.lock().pop_front() {
                write.set(value);
            }

            if channel_closed.get() {
                cx.dispose();
            }
        });
    }

    let send = create_ext_action(cx, move |_| {
        channel_closed.set(true);
    });

    std::thread::spawn(move || {
        while let Ok(event) = rx.recv() {
            data.lock().push_back(Some(event));
            EXT_EVENT_HANDLER.add_trigger(trigger);
        }
        send(());
    });

    read
}